One small cohort is behind most of the pancreatitis alarm
In 613 semaglutide users, the pancreatitis hazard ratio was 9.09, with a confidence interval running from 1.25 to 66. The same study recorded zero bowel obstructions.
What the study found
The famous ninefold pancreatitis figure rests on 613 people
This is the study behind most of the public alarm. Against another weight-loss drug, 613 semaglutide users had a pancreatitis hazard ratio of 9.09, with a confidence interval running from 1.25 to 66, and recorded zero bowel obstructions, so the 4.22 quoted for obstruction is not theirs.
The caveat · Prescribed people may differ already
It is observational, so people prescribed these drugs may already differ from the comparison group in ways no adjustment removes. It was published as a research letter, so the methods are described only briefly. The authors say they cannot be certain every prescription was for weight loss. Reported incidence in the semaglutide group was 4.6 pancreatitis cases per 1,000 person-years.
What we don't know
The ninefold figure cannot stand alone: its confidence interval is wide enough to hold almost any answer, so this cohort cannot say how large the pancreatitis risk is. The randomised trials are much the stronger evidence.